function fn(person) {
    person.age = 19
    person = {
        name:'aa',
        age: 19
    }
    return person
}
const p1 = {
    name:'bb',
    age: 18

}
const p2 = fn(p1)

console.log(p1); //{name:bb,age:19}
console.log(p2);  //{name:aa,age:19}

